1. Field of the Invention
This invention relates to a liquid applicator and a liquid supply method to be used in a liquid applicator.
2. Related Background Art
Probes that can uniquely be bonded to a target substance having a specific base sequence such as a short fragment of single-strand DNA and are labeled with a radio isotope or a fluorescent substance are being utilized for gene diagnosis and analysis of the base sequence of a genetic DNA. Like ink, liquid containing such probes can be ejected by means of a printing technology such as ink-jet printing technology.
As means for providing a plurality of different probes simultaneously, probe carriers such as DNA chips on which a probe array is formed by arranging, on a medium such as glass substrate, a multiple of probes that can be bonded to different target substances to be detected are attracting attention.
In recent years, research efforts have been paid to apply techniques relating to ink-jet printers to the manufacture of probe carriers. Currently, it is possible to make a single probe carrier to securely hold tens of thousands of different probes. An ink-jet printer can eject a very small ink droplet from a nozzle and precisely and securely deposit it at a target position on a recording medium. Thus, a high density probe carrier can be manufactured at a time by applying various kinds of probe-containing liquid in place of ink.
A method comprising a series of steps for manufacturing a probe array by supplying probe-containing liquid from a well plate to the reservoir of a liquid ejector, which operates as liquid applicator, and ejecting probe-containing liquid from the liquid ejector has been devised. It is assumed for this technique that a certain number of arrays are manufactured continuously. This technique is described in Japanese Patent Application Laid-Open No. 2000-513266 and U.S. Pat. No. 5,958,342.
Japanese Patent Application Laid-Open No. 2002-318232 discloses a method of efficiently manufacturing probe arrays, using a liquid ejector comprising a number of sets of a liquid reservoir that stores probe-containing liquid and a liquid ejecting nozzle that communicates with the liquid reservoir, as corresponding at least to the number of probes.
Japanese Patent Application Laid-Open No. 2002-296287 describes an applicator to be used with tanks that store probe-containing liquid and to which respective bar code seals are applied in order to control the liquid in the inside by using the bar codes so that the tanks can be arranged reliably as corresponding to the array.